Electric band tightener



' 5 Sheets-Sheet 1 June 19, 1934. F P. PRINDLE ELECTRIC BAND TIGHTENERFiled Jan. 18., 1932 nl V vIllll I' @n June19, 1934. `F P; PRINDLE. A1,963,593 ELECTRIC BAND TIGHTENAER I Filed 112111.18', 1952 v ssheets-sheet 2 a@ /My June 19, 1934.

F. P. PRINDLE 1,963,593

ELECTRIC BAND TIGH'IEIXER SSheets-Sheet 3 Filed Jan. l, 1952 PatentedJune 19, 1934 UNITED STATES ELECTRIC BAND TIGHTENER Frank R'Frindle, NewBritain, Conn., assignor to The Stanley Works, New Britain, Conn., aoorporation of Connecticut Application .tammy 1s, 193s, sei-n1 No.587,285

8Claims.

(Cl. 25H1) The present invention relates to tools or de- Fig. 3 is aside elevation of the forward end of vices adapted for use in theapplication of metal bands or metal straps to boxes, packages, bales,

cargoes, and the like.

An object of the present invention is 'to provide an improved device ortool which may be placed against or on a box, bundle, bale, cargo,

or the like, for example, and gripping the endsl of a metal strap ormetal band encircling the box l and which when actuated willautomatically draw' the strap taut to a desired and predeterminedtension and thus offset the necessity ofguesswork and irregularities inthe operation.

. Another object-of the present invention is to u. provide a device ortool of this character which is relatively'simple, compact and light inweight,

which may be vapplied and controlled by hand,-

and which is so constructed that the'metal bands or metal straps may bevery easily and quickly n tightened with but little effort or fatigue onthe part of the operator.

lAnother object of the present invention is to provide a motor-driventool with a winding drum so operated by the motor as to draw the bandtaut to a desired predetermined tension and maintain the band at suchtension without increasing the pull thereon until two or morethicknesses of the band may be joined,.secured, and sealed in place.

A further object of the ypresent invention is to provide a metal band orstrap applying tool lof thetype having an electric motor and a rotatableband engaging element projecting l.from one side of the tool for quickand easy attachment to an-end of the band, and to provide an improvedquickly releasrable grip lock at said side of the tool for anchoring theother end of the metal band so that the bandmaybe quickly andeasilysecured at the opposite ends to the tool at one side of the latter.

Other objects will be in part obvious, and in I y part pointed out morein detail hereinafter.

' 'Ihe invention accordingly consists in the features of construction,-combination' of i elements and arrangement of partslwhich. will beexempliiied in the construction hereinafter set forth and the scope ofthe application ofwhich will be indicated in the appended claims.

In the drawings, wherein'like symbols-refer to like or correspondingparts throughout the several views, A

Fig. 1 is a, side elevation of a metal box strap or band applying toolconstructedv according to 'th'e'present invention;

I 1153.2isatopplanviewofthesamo;l

the tool showing the means for engaging the opposite ends of the strap;l

Fig. 4 is a transverse section taken through the tool substantially yonme uns 4-'4 or Fig. 1; 60

Fig. 5 is a longitudinal section, enlarged, taken through the forwardpart of the tool substantially on the line 5-5 of Fig. 2;

Fig. 6 is a detail enlarged horizontal section taken through theanchoring device or clamp for 65 holding one end of the band, thesection being taken substantially on the line 6-6 of Fig. 1;

Fig. 'l is a .view looking at the forward end of the worm 25; and K Fig.8 is a view looking at the rear end of the 70 sleeve 31.

Referring now to the drawings, the tool is shown in the present instanceas of the portable type and includes a generally cylindrical motorcasing 1o and a housing 11 in une with and secured 75 to the forward endof the casing l0. The housing is generally of rectangular shape and atits rear end has an integral circular plate portion 17 which is securedto the forward end of the motor casing by screws 17. The numeral 12designates 80 a handle located above and extending longitudinally of theframe composed of the casing 10 and the housing 11. l The handle may beof any suitl able construction and shape, and it is here shown as beingprovided with a trigger 13 adapted for 85 closing an electric circuitthrough an electric motor 14 mounted in the motor casing 10. An electriccable 15 is connected to the rear end of the handle, as shown, or may beotherwise led to the motor.

' The motor casing, by preference, is of cylindrical construction, andhas at its rear enti a cap 16. The cap at its lower portion isflattenedout so as to provide a foot or rest 16. A train of'gears 18 is locatedin the motor casing between the motor 95 and a driven, shaft 19 which,as shown in Fig.

5, has a bearing in a bushing 20 iitted in a boss or nose 21 projectingforwardly from the front wallv of the motor casing. Suitable thrustbearings 22 are provided between the forward end of 100l the boss and ahead 23 formed on the shaft. The shaft extends forwardlyv in parallelismwith the motor shaft and through the upper rear portion of the housingl1. About this shaft is a driving worm 25 having recessed flanges 26and2'1 at its 105 opposite ends. The ange 2'!4 embraces a bearing- 28mounted on the shaft 19 for supporting the rear end of the worm, and thebearing 28 is also adapted to take up rearward end thrusts imposedv-uponthcworm As|howninng.7.thefront ilo nange 26 is provided with anumber of separate pockets 29, and these pockets are adapted topartially receive balls 30. Surrounding the forward end of the shaft andmounted for sliding movement thereon but keyed against turning movementrelative thereto is a sleeve 31 having in its rear face arcuate grooves31', as shown most clearly in Fig. 8. In the present instance, theforward end of the shaft is squared, and the sleeve 31 has acorresponding opening through which the shaft extends. The sleeve 31 isrotatably supported by a bushing 66 having a driving fit in the forwardend of the housing. This sleeve 31 constitutes a clutch member, and isnormally urged towards the worm by a spring 32 surrounding the forwardend of the shaft and backed up by an adjusting nut 33 threaded orotherwise suitably secured upon the forward extremity of the shaft 19.The spring 32 is adjusted so that there is a driving relation betweenthe sleeve and the worm until the strap is drawn about the box under thedesired tension and then, owing to the shape of the grooves 31', thesleeve may rotate relative to the worm without further driving the wormbut at the same time holding the worm against retrograde rotation.

The housing 11 carries a transverse shaft 34 to which is keyed orotherwise fixed a worm wheel 35 which meshes With the worm 25. Thetransversely extending shaft 34 carries upon one end a metal strap orband winding drum 36. This drum 36 may have a bearing at its inner endin the side of the housing 11, as shown in Fig. 4. The other end of theshaft has a bearing in a bushing 35 which is driven into an opening inthe other wall of the housing. A thrust plate 34 is secured to theshaft. The drum 36 projects laterally from the tool and is provided withrounded or otherwise suitably constructed peripheral or exteriorsurfaces upon which the diametrically extending slots 37 for receivingthe free end of the band so as to anchor the free end upon the drum totension the band when the drum is turned.. It will be noted that theslots 37 open from the outer end of the frame so that the band may beinterlocked with the drum by an edgewise movement of the band. 'Ihisadmits of easy positioning of the band on the drum and the removal ofthe band when required.

A plate 38 is secured to the bottom of the forward end of the housing 11and has a lip 38' in line with the projecting end of the drum 36 so asto guide the overlapping ends of the band as the latter is drawn taut bythe drum. This plate 38 also constitutes a foot or rest.

The housing is also provided with a lip or clamp plate 39 spacedrearwardly of, but in line with, the lip 38. Arranged above the lip 39is a transverse shaft 40 mounted in a bushing 41. This shaft has anon-circular section 42 'at the remote side of the tool and over whichsection is interlockingly engaged a spring holding plate 43 having anoutturning lug 44 against which is seated one end of a coiled spring 45.The spring is mounted upon an outward projection of the shaft, and theother end ofthe spring engages against the plate portion 17 of thehousing; thus the shaft is normally urged clockwise, having reference toFigs. 1 and 3. The opposite end of the shaft 40 is provided with anon-circular portion 47 upon which is mounted a release lever 48.

. The lever 48 extends upwardly along the operating side of the tool andis provided with an abutment shoulder 49 adapted to contact with anadjustable stop 50 which may be in the form of a cap screw and a shim orwasher 5I beneath the head of the screw. The screw 50 is carried by theplate 17. The upper end of the lever 48 extends to a desired height andis offset forwardly so as to lie closely adjacent to the forward end ofthe handle 12 and is provided with an inwardly extending ange 52providing a broad surface against which pressure may be exerted forswinging the lever 48 forwardly and turning the shaft 40 against thetension of the spring 45 and the band.

The shaft 40 is provided, beyond the noncircular section 47, with aneccentric or cam portion 53 upon which is pivoted a presser foot orclamp 54 extending downwardly toward and registering with the plate 39.The latter end of the presser foot 54 is provided with band grippingteeth 55 which are inclined in a general forward direction and adaptedto grip the band and bind it against the plate 39. The clamp 54 isinclined forwardly from the eccentric 53 and the latter is so spacedwith respect to the plate 39 that when the operating lever 48 is in thenormal position shown in Fig. l the teeth 55 may engage that plate. Theclamping member 54 is normally urged downwardly and rearwardly by aspring 56 interposed between the front of the pressure plate and a stud57 projecting from the housing 11. The backward swinging movement of thepresser foot 54 is limited by a stop 58 projecting forwardly from thelower end of a bracket 59 secured to the face of the plate 1'7 by screws60 or the like. A shim or spacer 61 maybe placed between the plate 17and the bracket 59 to properly locate the shoulder 58 with respect tothe frame and the lower edge portion of the clamping member 54. Theturning of the shaft 40 in a counterclockwise direction is adapted tolift the clamping member 54 from the plate 39,

as shown in Fig. 3 and the stop 58 limits the rearward swinging of theclamping member 54 under action of the spring 56 and guides the clampingmember 54 toward the plate 39 when the clamping member is again lowered.With this arrangement, when it is desired to secure one end of the strapto the tool by means of the clamp 54, it is merely necessary to bringthe strap to a position above the plate 39 land then move the strapedgewise towards the tool while at the. same time giving it a slightforward movement. In this operation, the strap will move the clampingmember upwardly and forwardly a sufficient distance to permit insertionof the strap between the plate 39 and the member 54. Now, when the strapis tensioned, the tendency is to pull that end of the strap which isclamped in place rearwardly, thereby causing the teeth 55 to bite intothe strap and hold it very tightly. When it is desired to release thestrap, it is merely necessary to move the lever 48 forwardly, a stepwhich does not require much 135 force owing to the manner in which theclamping member is mounted. By providing a proper number of shims 51 and61 or changing the thickness of the shims,'the setting and operation ofthe clamp may be readily adjusted.

For the purpose of reinforcing the connection between the housing 11 andthe motor casing, a dowel or cross pin 63 is secured transverselythrough the rear end of the housing and through arecessed or groovedportion of the boss 21 so as to rmly hold these parts together. Withthis arangement, some of the strain is taken off the integral fiange orplate 1'?, thus guarding against breakage or cracking of that plate.

In operation, a metal strap or wire is engaged 150 about a box, a bale,a bundle or the like and one end S of the strap (see Fig. 3) is insertedbetween the plate 39 'and the clamp 54 by an edgewise lateral movement,as previously described. The extreme portion of this strap end extendsover and forwardly of the lip 38'. 'I'he other end S of the strap isbrought over the lip 38' in overlapping relation to the strap end S andis engaged in one of the slots 3'7 of the drum 36. The strap ends mayhave been threaded through a seal (not shown) positioned forwardly ofthe lip 38. The operator now operates the switch trigger 13 so as tostart the motor 14 and the shaft 19 with its clutch sleeve 31. 'I'heclutch sleeve, through the balls 30,. turns the worm and rotates thedrum shaft 34 through its worm gear 35. Thus, the

drum 3S is turned so as to wind the free end of the strap thereon anddraw the strap under tension about the package or box. When the band isdrawn taut to the desired tension, the clutch sleeve 31 is retractedagainst vthe tension of the spring 32 so that the drum shaft 34 is notfurther driven even though the motor 14 may continue to operate.

As many changes could be made in the above construction and manyapparently widely different embodiments of this invention could be madewithout departing from the scope thereof, it is intended that all mattercontained in the above description or shown in the accompanying drawingsshall be interpreted as illustrative and not'in a limiting sense.

The title of this application, Electric band tightener, and the preambleof the claims, In a box strap tightening-device, are used forconvenience only, it being understood, of course, that the device may beused as a tightener for tensioning metal about boxes, bales, bundles,cargo, or the like.

It is also to be understood that the language used in the followingclaims is intended to cover all of the generic and specific features ofthe invention herein described and all statements of the scope of theinvention which, as a matter of language, might be said to falltherebetween.

I claim as my invention:

1. A box strap tightening device comprising a casing having at itsforward end a forwardly extending boss, a housing having a plate portionat its rear end secured to the forward end of said casing, said housingalso having an opening closely receiving said boss, the Awall of saidopen-- ing and the external wall of said boss having complementarygrooves forming an opening for a cross pin, a cross pin in said openingformed by said grooves, a motor in said casing, a shaft connected tosaid motor and extending through said boss, a winding drum journalled insaid housing, and a connection between said shaft and drum.

2. A box strap tightening device comprising a casing, a housing securedto the forward end of said casing, a motor within said casing, a shaftjournaled in and extending longitudinally of said housing, a drivingconnection between said shaft and motor, a ltransverse shaft journaledin said housing and having a winding drum at one end, a worm wheelwithin said housing and on said transverse shaft, a worm. about andadapted to rotate relative to said longitudinally extending shaft andmeshing withl said worm wheel, asieeve adapted to slide on but rotatablewith said longitudinally extending shaft and `opposed to one end of saidworm, a ball clutch between said worm and sleeve, a spring about saidshaft and normally urging said sleeve towards said worm, and a nutbacking up said spring and adjustably mounted on the forward end of saidlongitudinally extending shaft. y

3. In a box strap applying tool, a framehaving a projecting lip, a shaftjournaled in the frame and having an eccentric portion located abovesaid lip, a clamping member journaled on said eccentric portion andadapted to normally cooperate with said lip to clamp a strap in place, aspring associated with said shaft and normally turning the same in adirection to engage said clamping member with said lip, a second spring4normally urging said clamping member in a direction opposite to that inwhich said rst spring rotates said shaft, and an operating leverconnected to said shaftfor turning the same in a direction to raise theclamping member from the strap. v

4. In a box strap applying tool, a frame having a projecting lip, ashaft journaled in the frame and having an eccentric portion above saidlip, a clamping member freely pivoted on said eccentric portion andcooperating with said lip, said clamping member, when in operativeposition, being forwardly inclined, a spring normally turning said shaftin a direction to bring the clamping member into operative relation tosaid lip,

a second spring engaging said clamping memshaft for turning the same ina direction to raise said clamping member from the lip.

5. In a box strap applying tool,a frame having a projecting lip, a shaftjournaled in the frame and having an eccentric portion above said lip, aVclamping member freely pivoted on said eccentric portion and having atoothed surface adapted to cooperate with said lip to clamp a straptherebetween, said clamping member. when in clamping position beinginclined forwardly with respect to said shaft, a guide carried by saidframe rearwardly of said clamping member and against which, the clampingmember is adaptedto engage when the same is raised, a spring associatedwith said shaft and normally-turning the guide behind said clampingmember and against,

which said clamping member is adapted to engage when the same is raised,means for adjusting said guide relative to the clamping member, a springassociated with the shaft and normally turning the same in a directionto engage the clamping member withV the lip, a second spring normallyurging the clamping member towards the guide, an operating lever fixedto the shaft, and an adjustable abutment for limiting the extent ofmovement of said operating lever.

'7. A box strap tightening device, comprising a motor, a drive shaftconnected to said motor, a driven shaft, a worm wheel fixed to saiddriven shaft, a winding drum fixed to said driven shaft, a worm'aboutand adapted to rotate relative to saiddriveshaftandmeshingatalltimeswiththe worm wheel a yieldable driving connectionbetween said worm and said drive shaft. said worm being held againstlongitudinal movement on said drive shaft, whereby the worm wheel anddrum will be held against retrograde movement when the drivingconnection between the drive shaft and worm is broken.

8. A portable self-contained power operated box strap tightening device,comprising a motor casing, a housing secured to the forward end of, andin line with, said casing, a handle on the top of said casing andextending longitudinally thereof, a motor within said casing, a driveshaft connected to said motor and disposed within

